M923a2 fuel problem

74M35A2 said:

I wish this guy was my brother.

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Yeh we would be great... “I didn’t put fuel in the truck, I thought you put fuel in the truck!”

The sister jokes would be a little more awkward though.

Blarsen said:

Took it apart and the connection was partly soldered so I re- soldered it and primed the truck, run for about 5 minuets and died again... I am at a loss now..

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Forget the soldering and BRAZE that joint....these trucks vibrate a lot, and the vibrations will cause the soft solder joint to crack again and either allow air to be sucked into fuel line or (better yet, ask me how I know) break off and the pickup tube will fall off into the farthest reaches of the fuel tank.

Once original is removed, I would probably only re-install a newly fabricated one. Can be bought or made, people here have done both, successfully. For anybody doing this on a cargo bed M939 series, the tank or bed need to be pulled for enough clearance to remove the tube. The stock top fitting is an inverted flare, which is somewhat of an oddity. More common for a replacement is a male flare, known as a JIC or -AN fitting. In this case, a great time to replace this hose at the same time.

Blarsen said:

Thanks so much for all the great info, new soft fuel lines have been ordered and I will update you when they get here..

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Any luck yet?

Sorry no luck yet, I ordered the correct hose but ordered 5/8 fittings and I needed 1/2... so they are on there way now..

I have stainless tubes ready to go if that helps. The fitting end is male JIC so it would be the time to ditch the copper fuel tubes and go full push lock. Hope you get it figured out.

Any updates?